Experiments are being done to elucidate the relationship between structure and function in the ribosome of E. coli. Several strategies are being used to identify ribosomal components with the functions they perform. Crosslinking reagents are being used to attach protein factors to the ribosome thereby allowing the identification of the proteins involved in binding factors to ribosomes. Photoactivated nucleic acid analogues are being used to affinity label the tRNA and mRNA binding sites. The functional role of thiol groups are also being examined by standard protein chemical techniques. Work is in progress to use neutron scattering to determine the three dimensional arrangement of protein subunits in the ribosome.